Safe to use expired Algaefix?

I wouldn't use it, expired or not. You need to look at what may be causing the problem. Too long of lighting, too much ferts in the water etc. Try a 3 day black-out, with a couple before & after water changes to see if that helps. Tell us all about your tank, lights, plants, maintenance, ferts etc.
 
I have no ferts or co2, it's a 46 bow with 110w of 6700k lighting over it. Fauna stock is light simply because everything is very young/small (guppies, baby angels, otos and the like). Tank has been set up since about March. It seemed to start getting cloudy once I removed about 1/3 of the plants 3 mos. ago, and even cloudier 3-4 weeks back when I removed even more plants and changed the positions of others. I have been doing 30% wc's every week/week and a half. Filter is a Rena xp3.
 
I'd up the water changes & stop rearranging the plants, sounds like you're stirring up all kinds stuff. Cut back the lighting to ~8 hours & see if things clear up.
 
There's an experaion date on there for a reason :P
 
There are sale-by dates on water bottles, too, but water doesn't expire. :)

I was wondering if Algaefix could actually expire, but I don't wanna test it on my fish in case the outcome is bad. I have heard that it clears green water up pretty well though.

I'll do daily wc's and see if that'll help. Lighting is at 10 hrs. daily and controlled by a timer, but I'll cut it down to 8 hrs.
 
The FDA requires everything to have an expiration date by law. Its more about the bottle than the actual water.

Any quick fix product out there (like algaecides) are only masking an underlying problem. Sure, they may kill off the existing algae and some spores, but if the conditions stay the same what keeps it from coming back?
 
Well I believe the problem is from me removing a lot of the plants, and like fsm said, the level of nutrients is probably greater than what the current quantity of plants can handle. A quick fix would be fine in this situation, I think. As soon as my plants fill the gaps in and spread, this problem shouldn't pop up again (at least for the same reason).

I've been doing 30-40% wc's 2-3 times each week for the last two weeks, but it hasn't really cleared the water up, even a little. I'll try daily 40-50% wc's and see what comes of it.
 
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